Awwe that would make for such a sweet project with your wife!!! I hope she gets better too, unfortunate that she still isn't feeling well, I hope you can find the cause of her issues and eliminate whatever is bothering her.
I suppose I may be shy but I still have a bold personality that doesn't go un-noticed so it's easy to get strangers to talk to me. I do have my fair share of chicken out moments in other areas of my life that I have gotten over and bit the bullet and succeeded. Fortune favors the bold. Follow your instincts and don't over think it. If you are unnatural, ppl will sense that too and be the same. Each time you chicken out, your practicing to go a step further next time at some point you'll be there as long as you progress everyday...it's like learning how to weld...baby steps.
One thing I can guarantee , sharing small meaningful moments with total strangers regularly is a rewarding experience for both sides and it's easy to connect with strangers when you let the big fancy camera do some of the talking, ppl love to be part of something even if they don't know what it is as long as you find a way to connect with them instantly.